Roland Turner


Yahi Haze Mapping
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First Gpredict Session

For the first time since July I managed to get out and operate last night. Sadly I made no successful contacts: During the 20:56 - 21:08 pass of CUTE-1.7 + APD II (21° peak) my TH-F7E radio went into a mode that I've never seen before. By the time I'd worked out how to reset it without wiping its memory ("Fn+Pwr" for future reference...) the pass was over. The other two passes that occurred while... (more)

Crash-Only Software at Papers We Love Singapore

I gave an overview of Candea and Fox's Crash-Only Software at Papers We Love Singapore last night. The slides are a little spartan. (more)

Brexit, Interrupted (UPDATED - This approach won't work.)

Update: 2016-11-06 Writing up an idea in detail can be an effective way to share it, but also to more quickly discover any errors in it by giving others the opportunity to scrutinise it. In this case, a significant error in my understanding of the role of the Supreme Court has been pointed out to me, large enough that the approach described below clearly won't work. The only judicial function that the House of Lords... (more)

Simplest Possible Systemd Service

(Because almost every search result for this provides a lengthy discussion instead of a simple example...) In /etc/systemd/system/sleep-92951829.service : [Unit] Description=Sleep Demo [Service] ExecStart=/bin/sleep 92951829 [Install] WantedBy=multi-user.target $ sudo chown root.root /etc/systemd/system/sleep-92951829.service $ sudo chmod 644 /etc/systemd/system/sleep-92951829.service $ sudo systemctl enable sleep-92951829 $ sudo systemctl start sleep-92951829 $ ps -fC sleep (more)

PayPal problem VV44REXSG (KMM201394745V73460L0KM) and the lack of a Singapore remittance license

3 years ago, PayPal ceased handling payments from Singapore account holders to charities outside of Singapore. The cited reason is that PayPal does not hold a remittance license in Singapore. An important consequence of this is that payments from Singaporean PayPal accounts to any non-profit organisation outside of Singapore, charitable or otherwise, are prevented. Inconveniently, and despite the fact that this is not a secret at all, PayPal appears unwilling to correctly describe the reason... (more)

First successful satellite tracker test

(Photo: Darryl Ee 9V1DE) After successfully listening to FO-29 with a handheld satellite-antenna at Geekcamp last year, I realised two things: directional antennas are extremely desirable for satellite work, but holding and pointing the antenna array by hand is exhausting. I therefore decided to build a tracker that would automate the pointing and following work. The resulting system came together just in time for Maker Faire, so I conducted its first tests on site. It... (more)

Peering inside TLS traffic, server-side

In the easy case where I have access to the server and am able to tell the client to use a different TCP port: socat TCP4-LISTEN:7080,fork,reuseaddr OPENSSL:localhost:443,verify=0 & socat OPENSSL-LISTEN:7443,certificate={certfile},key={keyfile},fork,reuseaddr,verify=0 TCP4:localhost:7080 & iptables -I INPUT -p TCP --dport 7443 -j ACCEPT Some details: Verification is unnecessary when talking to localhost, although this could be readily tightened with a sutable cafile option. Using verify=0 in the OPENSSL-LISTEN section was an unexpected necessity; without it socat requires... (more)

gtk-creator-usb "Failed to install the bootloader"

Old-school solution: dd if=ubuntu-{version}.iso of=/dev/{device} After several failures and various blind alleys around disabling automounting, I discovered this comment which happens to describe exactly my sitaution (creating a 64-bit installer on a 32-bit platform): Right, this explodes because the architecture you're running on doesn't allow starting executables of the architecture you're trying to burn on the USB disk. Everything is obvious in retrospect... (more)

Installing yum-cron

From the school of "the purpose of installing packages is to clutter your filesystem with files that don't do anything" comes yum-cron. Why anyone would want this installed but not working is not clear to me, but: yum install -y yum-cron service yum-cron status | grep -q enabled || service yum-cron start chkconfig yum-cron on (more)